Attachment for lathes



S. C. BLISS.

ATTACHMENT FOR LATHEs.

APPLICATION FILED NOV- 20 1 918.

1,401Q954. Patented Ja1 1.3,1922.

.4 TS-SHEET I.

amnwtoi S. C. BLISS.

ATTACHMENT FOR LATHES.

APPLICATION FILED NOV. 20. I918.

1,401,954, Patented Jan. 3,1922.

4 SHEETS-SHEET 2- awvewtoz filvewmadi lzlss 38M, Mo l/14mg I V S. C.BLISS.

ATTACHMENT FOR LATHES.

APPLICATION FILED NOV. 20, 1918.

1,401,954. Patented Jan. 3, 1922..

4 SHEETS-SHEET 3.

' a nwutoz b law 00a 63 3/1155 S. C. BLISS.

ATTACHMENT, FOR LATHES.

wmwto c fiery/00 .Blllss M atmneq Speciiicatien o1! p a F i t-tteenresume jpplicatioir filed Novic nber 2t, 1918. ise i'a -nq; 25333-3;

I teeth: oftaps, cutters, -hobs, :mills,- etc.-,' 7 said attachment:beingjadaptedxto be; used": with lathes of standard type already in jservice or tube-originally:built-invwithisamd -:It"h asi for; itsobjectto-accomplish a rapid and accurately; controlled 'movementofanexternal? or internal thread. chasing or other tool; and to effect samewithxaiminimum of shock in that the novel construction permits of agreatly reduced weight of the parts, it a being understoodsthatthefcontrol is effected by means of a camwhich,inaccerdancer with thepresent invention, is not of the :'usual peripheral type: employed for-:this work but is: a'-tface;cam. "zlt lwillvb'e appreciated that inapparatus -'of .this character tlief accuracy of thei work requiredprecludesi the use of any cushioning device fbruabsorbinfg the shockresulting. ifrom' stopping of, the i-a idly moving too-1islidevin theproper position for chasing or relievir'ig and that thelack of any suchcushioning device imposes heavy stressesin parts *of the meehanism.Moreover, the time available for the'movement from one radius ofoperation to another is so short that the movement required must be veryrapid. A further object of the inven tion consists in providing a camwhose controlling surfaces may be readily machined to very accuratedimensions, and in so mounting the back face of the cam as to eliminateall bending strains of same and its carrying shaft, and to make possiblethe ready renewal of all surfaces subject to shock. This is attained byproviding a large bearing area, not possible with the peripheral camsheretofore employed wherein contact in the action is substantially alonga line and causes rapid wear. This latter action resulting in unduewear, and the fact that heavy parts are necessary and cause heavy shockdue to impact of the said parts, are par- ,correspon ticularlyiobjectionable features of the apparatus-asheretofore employed,- P1 ii.The nature of the-invention-will be best understoedwhen desciibed in 3connection with the; accompanying tdravvings, illustrating the*invention-embodie'd in a device for chasing interrupted threads on 1 gun breechplugs,and'inWhiCh wwz-r-a; 11 f? e Fig 1- is front elevation Loff-thefactive -portion 1 of--. a: lathe 'lwithsaid device adapted thGIQtQ;.-EiSFig.= 2 isa plan thereofz 3 1, LF" g. 3 isia: section: taken 'oi-i theline 3 3,

2 lookingin the direction" ofthe" arrows. :F1g-.:'4 is a fragmentarytransverse section taken 'oIr't-he line 3;" .7 FigI :5 is a diagrammaticview, illustrating theactioniofthe devicez FF? Fig; 6' 'sf'anien'dview-of a "breech"-plug. Similar? characters of {referenced'eslgn'ate Qingparts 'througheut the 'several VIQWSi-H 1 Referring "t d the a g-1aattest the lathe'bed upon: which there iscaused to travel; either cautom atica'lly or me nuall y; the

.usualtarriage l lprbyided with, a cro'ss slide .11 ea salsa =12; ifAlongf the lathe;'pr eferebly-at the back which: is idesigiid 'to'-berotated "111 21113? si iit able manner from the head-stockspind'lef16 of: the: latheg jas "for example-through 'intermediate gears :17Between"i -the head=stock from the shaft 15 through bevel gears 25,

is a cam shaft 26 through whose rotation the controlling movement forthe operations hereinafter referred to is obtained. To this end, theshaft 26' extends into the cross-slide 12; that 1s to say, a flangedsleeve 27, keyed to said shaft, is caused to rotate within a bushing 28of the said cross feed slide. The i bushing 28 is provided with anoutward flange 29 between which and the flange 30 of the sleeve 27 ismounted a face cam 31, the back "of which cam abuts the flange 29 and isfreely. rotatable with respect thereto. The

cam is secured to and carried by the flange 30 so as to rotate, throughsleeve 27, with Y The slide 12 the em Shem; Ii h s is'causedtd partakeof-the' motie cam shaft-26, and at the sameti neellpws o the cross feed0f 'tlie f s l id relatlvelfi' tm said camshaft. V

slide carries a suitable 'to0l36 designed to tatedp In addition;tozitslengitudinalzffeedy and erossifeedfimevements through slid -12 for thispurpose, havingwalmeutwardttubular,

' v extension; 38 E intd whiehr pnej eets: a* retl'r 39 i i: bnaeketetl: extendingis upwagdlys from; slide 1 '12. Between the'headf42 ofsaid tubule-Heir tensiqn; and? the inner; and 9t: 11nd; 39,-=which -,ispr.Qvided-? withkas-head ompist' 1m coil maintain abeutszimeglandydmiyentheiiehy; a bxosslslide mgun ingssaidssleey a. 1 mi;sleevewandg bfiiLIf-i the:

theltoolr slide 35.. isfeauseda toa be raipidlymnd accuratelyneciprqevted' toward? and away from i the; work F1118; im aecordenee:with; the; 7 design efiz ther calm 3:1 iwhosewface is foxzmed A to suitthe charaeter;0i thwWdrkwinfihamh I This is efi'eetedgbywpzowiding the;smidajslide; Y 3543b itsunden simfeeemwithk as eam bleck iff engagingthe face'h0fca1n'31 to thereby tz ol the inand-Out'. posit-iom ogfthe;slide; 1 and: its t0o1f 36, -thno1ighgthe-notation Of the. cam andin; accordance with the; pesitiion at J the Wonk-:1 As: isxheiaeinshewn, i theeam; a ets I to force the tool 36 owned the-w0rlm18 aind'isi' retmtned by resilie t: means, the slide u35,

tetedthel-tebyr,

bysaid cam andcarried by said cross :'j "2. 111? pwc-u wemm characterset wei sleevenbhut" same and driven thereby,"'a,

,Cros s] feed; slide, a biishing mounted within said slide about saidcam sleeve and" within whinhesfihei lattls is; adapted. to rotate, saidbushing being provided with a flange at its outer end, and 311 face; cam'netained-tbetween thetfinsnges ofi seidvbushingi the} flange; of swidaeamssleeve. end'driven ey said" sleeve H -eppamtuswof:they'lchenaeterset sleeve about." -'sarme;"'a1nd=1 ffdrlive'n thereby: a

eutemendgs andhi face eamyretained between thelflangeefisaaidr bixshingzand the flange ef' seidaeamsreeye, bea ri ng againstgtheaflange eafitheyfonmen ande oer-Itiedfbh the: flange: of the: tterrtoifrofiatexwithi theecam-i sleeve;

suitmbly drivem camshaft;- a-fleng'ed' dresssi-feedllslide,rwzibushingirnounted within V 'bushing kbei-ng pnevided rwithgafiaingeeaflits 43.1;ln ap mm m he character set 45mm a suitablytdriweneemisha tg mime em m eress 'feedgslidewithinwhich said eaml shaft'ijsj'l etatably mbnntedy a tool slide ceil 'm 'b'y saiid" aeei carnitesmove thea said? tofoF slide mohnte Q, t l em ia e th si (1" saidncfio'ssfedi slid, avcalm byi said-i tool sliderandisaetueted ink enew;dihe'c'tiem." at bracket} secured :to; the icross feed slide; a; tubularmemberf'eam'iedibjr said? te'o'lzsl ide-,i haqxiingeej rodextendingthere iseidfi:braekemrendra coil spring in h eutasaidrodwithimsaidi-tlibizlar 'meinlie ,vbneven d thereof bearing against: anends: at saidzie andftheketheis"againstz an end of smidwtubu 50 V e r Ii V n ,feflh. q;;su itebly driven camshaft, a flanged r eerries at itsupperpo'rtibn the 12 ide.fi lwhiehm e m menable kright angles tethemotibn of thi'lZrOSSSITdB i e V 12 in a manner welhunnlersteedeThemed ceacta with the: Wonk ESgrasf thei'letteh is 1B0?

